The P53 rifle, which replaced the P51 in 1855, experienced numerous changes to its own ammunition throughout its life. Three of these improvements to the P53 bullets were the transition to wooden plugs over iron cups in 1855, a reduction in bullet diameter (to facilitate loading) in 1859 and a cut made in the paper cartridge which left a vertical mark on the bullet itself. To bring the P51 bullets up to date and match the progress of the P53, the latter of these was approved first to the P51, in December 1859. In February 1861 the two other improvements were approved, the List of Changes stating that the diameter of the bullet was taken down from 0.685 to 0.675 in (the first size reduction, made for the 2nd pattern had seen it reduced from 0.690 in to 0.85 in) and the wooden plug replacing the iron cup (four years after this was approved for the P53 bullet). The wooden plug was approved to be substituted for clay in December 1863. This set of changes have been grouped together here under the umbrella term ‘3rd’ pattern’: a verified example of a P51 bullet incorporating these changes has yet to be recorded, so as a result the information here is based on a lithograph presented in the excellent British Military Small Arms and Ammunition (by David Ibbetson), copied form the now defunct Woolwich Artillery museum archives. It can be imagined that use of the P51 in the 1860s was somewhat limited, and the rifle probably served as a reserve arm for emergencies, therefore not seeing very broad usage.
Official weight and dimensions (information from Royal Laboratory lithograph circa 1861, reproduced in British Military Small Arms and Ammunition and the List of Changes).
- Weight: 662 gn (42.9 g)
- Weight of wooden plug: 8 gn (0.51 g)
- Diameter: 0.675 in (17.2 mm)
- Length: 1.025 in (26 mm)
1st pattern conoidal, iron cup 1851
2nd pattern cylindro-conoidal, reduced diameter, iron cup 1854
3rd pattern, cylindro-conoidal, reduced diameter, wood/clay plug 1861
